I'm having trouble understanding how the responses act with each other. Here is an example.

Player A has these foundations:

Revenant's Calling x2

Inhuman Perception x1

Player B has these foundations:

Blood Runs True x3

An attack is placed in the card pool by Player A. Player B activates Blood Runs True responding to the card being played. Player A responds with Revenant's Calling.

Ok... from my understanding, at this point Player B cannot activate another Blood Runs True responding to the card being played because the first Blood Runs True has not been resolved. OR, is it correct that Player B can respond to the card being played even though the first Blood Runs True has not resolved?

Another question. If an ability is canceled, Revenant's Calling cannot be played after the negation? Only before the card is negated?

I know this post has many questions, so to sum up. How do responses work exactly. Can each player play a response as long as they have a response to play, or can a player only play a response to the previous ability being played?

Another questions about Revenant's Calling and canceling a card ability. If a card is use and then canceled, can Revenant's Calling be used to commit the card even though the ability is resolved?

Pepsicola said:

ok starting where i commented. The attack is not placed in the card pool until the CC (and additional costs) are paid. So player A attempts to play a card as a form, card is now in a transitional area.

Player B reacts to "Before a CC is made". (using BRT)

Player A reacts to "After your opponent plays an ability" (using Revenants)

So yes if you opponent had 2 BRTs, you could commit the 2nd before he could use it.

As far as negation, revenants reacts to an ability being PLAYED, not RESOLVED. So negation has nothing to do with it. You could Seal of Cessation their BRT, then react with revenants to commit their 2nd BRT, order does not matter. Either way revenants is played before the ability resolves. So in this example one player commits BRT, then you discard a card to react with revenants, commit their 2nd BRT, THEN reveal/draw.

Hope thats clear. And yes he would have to wait for BRT to resolve, thus bringing you back to the "before a CC is made" step before he could react with another BRT.

General questions can get a bit tricky to answer, but if you have any more specific card interactions post them up and we will try to make it clear.